Smith, who has experienced three known alcohol-related incidents in the past 20 months, is taking a voluntary leave of absence from the 49ers. Smith is eligible to return to action for the 49ers this season and there is no minimum length of time he has to be out, an NFL spokesman said.

“I am taking a leave of absence to address my health,” Smith said. “I am sorry that I have affected my team, my family and the organization. I will do everything in my power to handle this situation the best way possible. I appreciate the support of the 49ers and our fans.”

General manager Trent Baalke also provided a statement in which he expressed support for Smith’s decision.

"Aldon Smith is taking a leave of absence to address a personal matter,” Baalke said. “The 49ers organization both respects and supports Aldon’s decision and commends him for taking responsibility for his actions. The long-term well-being of our players is paramount and we will stand by Aldon as he works toward addressing this issue. Due to the private nature of the matter, we will have no further comment.”

Because of a short week, the 49ers may not fill Smith's spot on the 53-man roster until after Thursday night's game against the St. Louis Rams.